Example Python formatting and linting
Table of contents
The way python formatters work is similar, so an example is shown below for autopep8 and flake8, with docformatter and pydocstyle.
Usually -r indicates recursive, -i indicates in place, and any of these tools can be run with the -h flag to get more information.
Furthermore, most of these tools can be integrated into your favourite code editor.
Installation and running
python -m pip install yapf flake8 docformatter pydocstyle
export my_code_file_or_directory=var
python -m autopep8 $my_code_file_or_directory -r -i
python -m docformatter $my_code_file_or_directory -r -i --blank --pre-summary-newline
python -m flake8 $my_code_file_or_directory
python -m pydocstyle $my_code_file_or_directoryExample code
For example, this code does not look great:
"""Let's all write some really ugly python. We can start off with a line that is just way too long."""
import numpy as np
import matplotlib.pyplot as plt
from math import ceil, floor
from pprint import pformat
def main( ):
"""This calculates some mad stuff.
Parameters
----------
None
Returns
-------
tuple (list, int)
"""
foo = [((1+2 * 25) * i, 100) for i in range(0, 20) if i%2==0] # Here is a helpful message to explain this madness
bar = ceil( foo[3][ 0]* 2)
return sorted(foo, key=lambda x: x[0] % x[1]), bar * bar + 10
if __name__ == "__main__":
# If invoked as the main file, will call main()
result = main()
print("{}\nthe output from the main was long, but there it is!".format(pformat(result)))
user_inp = input("Would you like to see just how great that was again? (y/n)\n")
if user_inp=="":
print("Empty input, goodbye then!")
elif user_inp.lower()=="y":
print( "Too bad, good things only come once.")
elif user_inp.lower()=="n":
print("Oh right, very well :(")
else:
print("Sorry I didn\'t get {}, leaving!".format(user_inp))After running yapf and docformatter, the output is:
"""
Let's all write some really ugly python.
We can start off with a line that is just way too long.
"""
import numpy as np
import matplotlib.pyplot as plt
from math import ceil, floor
from pprint import pformat
def main():
"""
This calculates some mad stuff.
Parameters
----------
None
Returns
-------
tuple (list, int)
"""
foo = [((1 + 2 * 25) * i, 100) for i in range(0, 20)
if i % 2 == 0] # Here is a helpful message to explain this madness
bar = ceil(foo[3][0] * 2)
return sorted(foo, key=lambda x: x[0] % x[1]), bar * bar + 10
if __name__ == "__main__":
# If invoked as the main file, will call main()
result = main()
print("{}\nthe output from the main was long, but there it is!".format(
pformat(result)))
user_inp = input(
"Would you like to see just how great that was again? (y/n)\n")
if user_inp == "":
print("Empty input, goodbye then!")
elif user_inp.lower() == "y":
print("Too bad, good things only come once.")
elif user_inp.lower() == "n":
print("Oh right, very well :(")
else:
print("Sorry I didn't get {}, leaving!".format(user_inp))Formatting and linting result
Then, running flake8 and pydocstyle gives the following output:
➜ Temp python3 -m flake8 my_code
my_code/ugly_python.py:8:1: F401 'numpy as np' imported but unused
my_code/ugly_python.py:9:1: F401 'matplotlib.pyplot as plt' imported but unused
my_code/ugly_python.py:10:1: F401 'math.floor' imported but unused
➜ Temp python3 -m pydocstyle my_code
my_code/ugly_python.py:15 in public function `main`:
D401: First line should be in imperative mood; try rephrasing (found 'This')(Photo by Chris Ried on Unsplash)